| 摘要 |
PURPOSE:To shorten drawing speed of phase servo as far as possible by making comparison of a phase detection signal of a tape and the phase of a reference phase signal at a period much shorter than that of the reference phase signal corresponding to running speed of the tape. CONSTITUTION:A frequency generator 11 that sends out a frequency pulse signal S11 having frequency proportionate to rotation speed is provided in a capstan motor 7, and the frequency pulse signal S11 is fed back to a speed servo circuit 6 and a phase servo circuit 5. Frequency of the signal S11 is so selected that it is much higher than that of the referense signal S2, for instance, several tens times (hundreds - thousands Hz). Phase of signals S11 and S2 is compared by a phase comparator circuit provided in the phase servo circuit 5, and phase of the running tape is corrected by this differential signal. |
